|Age||17-18 (was 17 before The Disappearance of Haruhi Suzumiya|
|Occupation||Student (grade 11-12), SOS Brigade Honorary Consultant, affiliate of The 'Agency'|
|Introduced In||The Boredom of Haruhi Suzumiya|
|Last Appearance||The Surprise of Haruhi Suzumiya|
|Voiced by||Yuki Matsuoka (JP), Kari Wahlgren (EN)|
Tsuruya (鶴屋 Tsuruya) was born on December 6 and is Mikuru Asahina's best friend. She tends to be hyperactive and has a very loud voice. Tsuruya has long green hair and a prominent tooth. She is friendly and laughs a lot. Her sharp tooth gives her a idiosyncratic speech pattern, causing her to say things wrong and leave out syllables. Her speech is often accompanied with a lisp and her catch phrases: "megas" and "nyoro" (she also refers to the members of the Brigade in different ways, as in referring to Haruhi as "Haru-nyan"). She was named "honorary consultant of the SOS Brigade" by Haruhi. She appears in The Adventures of Mikuru Asahina Episode 00 and plays baseball with the Brigade in "The Boredom of Haruhi Suzumiya".
Tsuruya appears to be a quite athletic tomboy. She performed admirably (given the circumstances) in the baseball game, and various alternate versions of her have demonstrated strength and even hand-to-hand combat abilities.
At first, Tsuruya only seems like an excitable tomboy who loves to dive her head into fun things, like Haruhi; however, Kyon notices a distinct difference in that while Haruhi always pries into mysterious things and their qualities, Tsuruya only accepts that they are mysterious and simply has fun knowing that fact.
While being Mikuru's best friend, their opposing personalities tend to clash. Tsuruya is a loud tomboy who isn't afraid to take risks, getting dirty or playing sports. Mikuru, on the other hand, is a shy girly girl who dislikes risky activity, being bad at sports and squirming when a ball comes close to her.
Tsuruya helps the SOS Brigade in several occasions, like playing baseball in The Boredom of Haruhi Suzumiya, playing a minion in The Adventures of Mikuru Asahina Episode 00, letting the Brigade "borrow" a house for Snow Mountain Syndrome, and giving Haruhi a treasure map to have fun with (allowing the SOS Brigade to take the treasure provided that Tsuruya get only one tenth of it) in The Intrigues of Haruhi Suzumiya. In a sense, Tsuruya acts in a similar way to Itsuki's 'Agency' in that she helps entertain Haruhi. However, in The Intrigues, when Tsuruya takes in the Mikuru from eight days later into her house without even inquiring thoroughly why there is a second Mikuru and accepting Kyon's patched alibi that she is Mikuru's twin sister, Tsuruya tells Kyon that her only purpose in entertaining Haruhi is that she likes to see other people happy without becoming a "lead player".
To her, even though she knows that the members of the SOS Brigade are not "normal", finding the details is not important, and she only wants to see them smiling and having fun.
Itsuki later reveals to Kyon that it was never an original intention for Tsuruya to associate with the SOS Brigade and an error somehow occurred either when she was placed in Mikuru Asahina's classroom or when she was invited to compete in the baseball game in The Boredom of Haruhi Suzumiya. While Tsuruya's family is loosely affiliated with the 'Agency', the Tsuruya family completely consists of humans, and while the family does not inquire into the 'Agency', the 'Agency' does not inquire into the Tsuruya family either. Kyon thus perceives Tsuruya as simply an excitable girl with a cheerful philosophy of life.
- In The Disappearance of Haruhi Suzumiya, Tsuruya was able to easily defeat Kyon in hand-to-hand "combat".
- In The Disappearance of Nagato Yuki-chan (manga) Tsuruya has demonstrated similar abilities, being able to match Haruhi Suzumiya in combat.
- In The Melancholy of Haruhi-chan Suzumiya Tsuruya has an intense and unexplained rivalry (involving outrageous hand-to-hand combat) with Sonou Mori.
- Tsuruya has a chibi version called Churuya in Nyoron Churuya-san. This version is obsessed with smoked cheese.
She also received two more character songs for the second season, Matsutte Matsutte! Irasshi~i! and Osawa ga Se no The End.